JP2000176315A - Cone stack centrifugal separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cone stack centrifugal separator for separating liquid. SOLUTION: A cone stack assembly 25 is attached to a shaft central tube 23 and a liquid inlet 82, a first passage 83 and second passages 84, 85 are formed to a base assembly. A bearing device 35 is positioned between a rotor hub 24 and the shaft central tube 23 and an impulse turbine wheel is attached to the rotor hub. Jet stream nozzles 27, 28 apply rotary motion to the cone stack assembly 25 and the liquid of the jet stream nozzles enters a cone stack centrifugal separator from a liquid inlet. The same liquid inlet provides the liquid passed through the cone stack assembly to be circulated. In order to eliminate an inlet turbulent flow and to enhance turbine efficiency, a honeycomb-shaped insert element is incorporated in each of the jet stream nozzles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates generally to the continuous separation of solid particles, such as soot, from a fluid, such as oil, by using a centrifugal field. More particularly, the present invention relates to the use of a cone (disk) stack centrifuge configuration in a centrifuge assembly that includes a turbine wheel for rotatably driving a rotor. The turbine wheel is driven by a jet nozzle tangentially aligned with the runner circular centerline.

[0002]

2. Description of the Related Art Diesel engines have relatively high performance air filters (cleaners) and fuel filters (cleaners) in order to prevent dust and the like from being emitted from the engines.
Designed to have Despite having these air cleaners and fuel cleaners,
Dust including wear debris generated by the engine is mixed into the lubricating oil of the engine. This wears out key components of the engine, and if the condition remains or is not remedied, the engine will be damaged. For this reason, many engines are designed with a full-flow oil filter that continuously purifies the oil as it circulates between the lubricating sump and the engine components.

[0003] Such full-flow filters have a number of design limitations and considerations, of which the typical limitations are:
Such a filter is capable of removing only dust particles in the range of 10 μm or more.
By removing particles of this size, catastrophic damage is avoided, but harmful abrasion is caused by small-sized dust particles that get into the oil and stagnate. In an attempt to address concerns about small diameter particles, designers have employed bypass filter systems that filter a predetermined percentage of the total oil flow. Combining a full-flow filter with a bypass filter reduces engine wear to an acceptable level, which is not the desired level. Since the bypass filter can capture particles of about 10 μm or less, combining the full-flow filter with the bypass filter provides a significant improvement over using a full-flow filter alone.

[0004] While centrifuge cleaners can be formed in a variety of ways, such as those shown in earlier designs, one product that represents a portion of the earlier design developments is the Somerset of Ilminister in the United Kingdom. Manufactured by Glacier Metal Co., Ltd. F. It is a Spinner II oil purification centrifuge provided by Hadgins. Spinner II is a registered trademark. Various advances and improvements to Spinner II products have
U.S. Patent No. 5,575,912, issued to Harman on November 19, 1996, and U.S. Patent 5,637,217, issued to Harman on June 10, 1997.
No. By reference to these two patents, the contents disclosed in these patents are incorporated herein.

Currently, engine operating phenomena occur that produce unacceptable levels of lubricating oil soot. Most of this lubricating oil soot needs to be removed from the lubricating oil. This is because soot causes wear and unacceptable wear can risk on critical engine surfaces and critical engine interfaces. As NOx emissions regulations become more stringent, delayed injection is widely used, possibly with exhaust gas recirculation or water injection to further delay combustion. This lowers the peak temperature and reduces NO
forming x. However, due to the delayed combustion, soot adheres to the exposed cylinder wall, and shifts to lubricating oil by the scraping action of the ring. According to engine data obtained by examining the soot of lubricating oil, 250
It becomes clear that it becomes about 7% with the operation of time. The lubricating oil soot is between 0.02 μm and 0.06 μm
Although relatively small in diameter, on the order of m, it does cause wear and at the critical high pressure / deep interface as found in valve train components. For more information on wear properties and wear, see SAE Publication No. 971631.

An important aspect of the present invention is the recognition that removal of very small soot particles by centrifugal filtration in a cone stack design or by conventional centrifuges generally does not work. One factor in this failure is the typical rotational speed at which the centrifuge is driven. Hero-turbin
e) The typical rotational speed for a centrifuge, i.e., a typical rotational speed, is about 5 for a rotor having a cone stack with an outer diameter of 4.65 inches.
000 RPM and an outer diameter of 8.89 cm (3.50
For a rotor with a cone stack of inches, it is on the order of about 7000 RPM. These rates are not fast enough to remove soot at an appropriate rate to control the deposition of soot in the oil. In order to effectively solve the problem of soot accumulation, a rotation speed about twice these rotation speeds is required.

[0007] The oil in the sump starts as clean oil and gradually accumulates soot as the engine runs over time.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to control the ratio of soot in sump oil. If the removal rate is equal to the add rate, an equilibrium is formed. What is important is the ratio of soot. The control equations are as follows:

Equilibrium soot concentration = addition speed / {(centrifugal removal efficiency). (Centrifugal flow rate)} Removal efficiency and flow rate are related so that just doubling the flow rate reduces the efficiency by half. An important matter is the removal efficiency. If this can be increased, the concentration of soot in the sump will decrease without changing any other factors or components.

With respect to current centrifuge designs, in view of the concerns and considerations discussed above, it is an improvement to devise a configuration suitable for generating even higher drive (rotational) speeds. According to tests, when the sump was circulated for 280 hours (engine off test), the level of soot in the lubricating fluid was reduced by driving the centrifuge at a rotational speed near 10,000 RPM. About 4.1%
It has been found that it can be significantly reduced from about 0.8% to about 0.8%. The present invention is an improved structure for a typical desired cone stack centrifuge that can generate desired speed of 10000RPM without the need increases above the operating pressure of 4.92kg / cm ² the pressure of the lubricating system (70 psi) I will provide a. Operating pressure range is about 2.812 kg / c
m ² (about 40 psi) to about 6.327 kg / cm ² (about 90 psi)
) Up to the upper limit.

One concern associated with this pressure range is that the bearings supporting the rotor must be designed to withstand and accommodate the pressure inside the rotor. Although journal bearings are preferred at these high pressure levels, these bearings have a rotational drag coefficient due to the viscous shearing of the thin oil film between the bearing and the shaft, so that the cone-stack centrifuge requires the desired 10,000 RPM (or Higher speed). By reducing the operating pressure inside the centrifugal rotor, roller bearings that can rotate at higher speeds with a much lower coefficient of rotation can be used.

[0012]

SUMMARY OF THE INVENTION A cone-stack centrifuge according to one embodiment of the present invention for separating particulate matter from a circulating liquid has a cone-stack assembly. The cone stack assembly includes a hollow rotor hub and is designed to rotate about an axis. The cone / stack assembly has a liquid inlet,
There is a first passage, a second passage connected to the first passage, and a base assembly defining a hollow base hub. The liquid inlet is connected to the hollow base hub by a first shaft passage. A shaft center tube is attached to the base hub and extends through the rotor hub.
As the cone / stack assembly rotates,
A bearing is positioned between the rotor hub and the shaft center tube. A turbine wheel is mounted on the rotor hub, and a jet nozzle is flow coupled to the second passage for directing a liquid jet to the turbine wheel to drive the turbine wheel. The drive of the turbine wheel imparts rotational movement to the cone and stack assembly.

A related embodiment of the present invention involves the use of a honeycomb insert incorporated at the inlet of the jet nozzle to eliminate inlet turbulence and improve turbine efficiency.
One object of the present invention is to provide an improved cone stack centrifuge.

[0014] Related objects and advantages of the invention will be apparent from the description below.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the accompanying drawings and specific language will be used to describe the same. Nevertheless, the scope of the invention is not intended to be limited thereby, and such variations and modifications of the illustrated apparatus and other uses of the principles of the invention illustrated herein. It will be understood that one of ordinary skill in the art to which the present invention pertains will normally be envisioned.

Referring now to FIG. 1, there is shown a cone stack centrifuge 20 according to a preferred embodiment of the present invention. The centrifuge 20 includes as its main components a base 21, a bell housing 22, a shaft 23, a rotor hub 24, a rotor 25, a cone stack 26, jet nozzles 27 and 28, a modified Pelton turbine 29, and the like. As described and used herein, rotor 25 includes a cone and stack assembly.

FIG. 3 provides a schematic plan view of the jet nozzles 27 and 28 and the impulse turbine 29. This figure shows the direction of the jets 27a and 28a leaving the jet nozzles 27 and 28, respectively. In the turbine 29,
A series of 18 buckets 32 arranged in a circumferential direction attached to a rotatable wheel 33 are provided. The jets 27a and 28a are directed tangentially to the wheel on both sides of the wheel and towards the center of the bucket. The bucket rotates into a tangential zone on the corresponding side of the wheel 33. The rotatable wheel 33 is fixedly and firmly attached to the rotor hub 24 that is positioned concentrically about the shaft 23. The rotor hub is attached to and supported by the shaft 23 by an upper roller bearing 34 and a lower roller bearing 35. Shielded to reduce flow through bearings
Sealed bearings are used instead of bearings.

Although the turbine 29 can be formed in various types, the preferred configuration for the present invention is a modified half-bucket Pelton turbine. Modified half bucket turbine 2
9 is shown in FIG. On the other hand, a conventional Pelton turbine 29a (split-bucket) is shown in FIG. The differences between these two turbine aspects are limited to the respective geometry of buckets 32 and 32a. Except that the split bucket type turbine 29a of FIG. 2 is used instead of the modified half bucket type turbine 29 of FIG.
1 and 2 have the same structure. Although the construction of the split bucket 32a is considered well known, the configuration of the modified half bucket 32 is unique in the present application. Referring to FIGS. 4 and 5, additional details regarding the shape and structure of each half bucket 32 are provided.

The cone / stack assembly or rotor 25 comprises, as major components herein, a base plate 38, a vessel shell 39, and a cone / shell.
It is defined to include the stack 26. The assembly including these main components is mounted on the rotor hub 24 such that the rotor 25 rotates as the rotor hub 24 rotates about the shaft 23 by roller bearings 34 and 35. Jet nozzle 2
Turbine 2 driven by high pressure flow exiting 7 and 28
The actuation of 9 causes a rotational movement to be applied to the rotor hub 24. When the jets 27a and 28a hit the bucket 32,
Each of the corresponding buckets is pushed and the wheel 33 rotates, sending the next bucket to the tangential point where the jet hits. This occurs cooperatively on each side of the wheel because the tangent points for jets 27a and 28a are 180 ° apart. The wheel accelerates and rotates based on the characteristics of the jets 27a and 28a and the dynamic characteristics of the turbine until a certain steady rotational speed is reached. Because the turbine is attached to the rotor hub 24 and the rotor hub is attached to the shaft 23 via bearings, the rotor 25 rotates at a speed indicated by RPM that matches the speed of the wheels 33 of the turbine 29.

In the preferred embodiment of the turbine 29, each bucket 32 (modified half-bucket type) has an ellipsoid-like profile and an exit angle of 10 ° to 15 ° at the edge of the ellipse. FIG. 4 shows a front view of one bucket 32. A perspective view of one bucket 32 is shown in FIG. The flow exiting the bucket is directed downward and away from the rotating rotor, thus reducing drag resistance due to droplet impact. The structure of the centrifuge 20 except for the part inside the base 21 and the lower part of the base plate 38 has certain features.
U.S. Pat. No. 5,575,912 and U.S. Pat.
The structure is the same as that disclosed in Japanese Patent No. 37,217. By reference to these patents, the contents disclosed in these patents are incorporated herein. More specifically, a radial outer lip 40 of the bell housing 22 is positioned on the upper surface of the flange 41. The interface between the radial lip 40 and the flange 41 is partially sealed by the addition of an annular intermediate O-ring 42 made of rubber. A band clamp 45 is used to complete and complement the sealed interface. Clamp 45 is positioned about lip 40 and flange 41 and includes an annular inner clamp 46 and an annular outer band 47. Tightening the band 47 reduces the inner diameter of the clamp, and the tapered sides of the annular channel 48 pull the lip 40 and the flange 41 axially toward each other, forming a tightly sealed interface. O-ring 42 is compressed by pulling lip 40 and flange 41 together.

The top of the bell housing 22 is provided with a cap assembly 51 for receiving and supporting the male screw end 52 of the shaft 23. Details of the shaft 23 are shown in FIG. The adapter 53 is provided with a female thread and has a flange 54, which is fitted through the edge of the opening 55 and pressed upwardly. Sleeve 56, O-ring 57, and cap 58 complete the assembly. First, the end 52 is screwed into the adapter 53, the O-ring is assembled, and then the housing and the sleeve are lowered to a predetermined position. Attach the cap and attach the cap assembly 51 to the shaft 23.
Then, it is fixed to the housing 22, and the band clamp is assembled and tightened in a predetermined position. Cap assembly 51
In order to smoothly rotate the rotor 25 at a high speed, the upper end of the shaft 23 is axially centered to support and stabilize the shaft 23.

At the upper end of the rotor 25, the bell housing 2
A mounting nut 61 and a support washer 62 are arranged between the second and the male screw ends 52. The annular support washer has a shaped shape that matches the shape of the upper portion of the rotor shell 39. A possible alternative to the present invention instead of using a separate component for the washer 62 is to integrate the support washer function with the rotor shell by manufacturing an impact extruded shell having a thicker cross section at the washer location. The upper end 63 of the rotor hub 24 is bearing-supported by the shaft 23 and the upper bearing 34, and has a male screw. Mounting nut 61 at upper end 6
3 to the support washer 62
And pull the rotor shell 39 together. Rotor hub 2
At the opposite end (lower end) 64 of the shaft 4 is a series of axial notches 6.
4a and a series of alternating outwardly extending splines 6
4b is provided (see FIGS. 7 and 8). This splined end fits snugly into a cylindrical hole 65 provided in the center of the base plate 38. The hole 65 is concentric with the hub 24 and the shaft 23, and fixes the hub to the housing and the base plate to rotate the cone / stack assembly concentrically about the shaft 23. The fit between spline ends 64 and holes 65 also forms a series of spaced outlet flow channels 66 by notches 64a and splines 64b.

A radial seal is formed between the inner surface 67 of the lower edge 68 of the rotor shell 39 and the outer annular surface 69 of the base plate 38. This sealed interface is partially closed by a snug fit and partially annular O
-Formed by using a ring 70; O-
Ring 70 is compressed between inner surface 67 and outer annular surface 69.

By assembling between the rotor shell 39 and the base plate 38 in combination with the O-ring 70, the inner volume 7 in which the cone stack 26 is accommodated is formed.
Form a sealed enclosure defining 3. Each cone 74 of the cone stack 26 has a central opening 75 and a plurality of inlet holes disposed adjacent the outer annular edge 77 around the periphery of the cone. Representative cones for this application are shown and disclosed in US Pat. Nos. 5,575,912 and 5,637,217. A typical flow path for rotor 25 begins with an upward fluid flow through hollow center portion 78 of rotor hub 24. This flow passes through the interior of the rotor hub and exits through hole 79. A total of eight equally spaced holes 7
9 (see FIG. 7). Flow distribution plate 8
0 is formed with vanes and is used to distribute the flow exiting the hub 24 over the surface of the uppermost cone 74a. The manner in which liquid (lubricating oil) flows over and through the individual cones 74 of the cone stack 26 is a flow path and flow phenomenon well known in the art. This flow path of the cone-stack assembly and the high RPM rotational speed allow small soot particles carried by the oil to be centrifuged from the oil and retained in the centrifuge.

The present invention relates to the design of the base 21 and the turbine 2
9, a method of sending fluid to the jet nozzles 27 and 28,
And the base 21, the turbine 29, and the nozzles 27 and 2
8 and a configuration of the shaft 23 that is designed to fit as desired. The base 21 has an inlet hole 82 and a main passage 83.
Are formed. Jet nozzle passages 84 and 85 intersect the main passage 83 at right angles. The passage 84 is defined by a mounting post 86 and the jet nozzle 2
7 to form a fluid communication passage. On the opposite side of the wheel 33 and the base hub 87 from the mounting post 86, there is provided a second mounting post 88, which defines a passage 85. Passage 85 provides a fluid communication passage to jet nozzle 28. In hub 87 of base 21,
A cylindrical hole 89 with an internal thread is provided. This hole intersects the main passage 83 at right angles. The base 90 of the shaft 23 is provided with a male screw, and is screwed into the hole 89 to be assembled. The base 90 is hollow and the passage 9
Define 1. This passage has a closed tip 92 and a throttle passage 93. The distal end of the passage 83 is
As well as the tip of the passage 85 (i.e., closed).

The rotor hub 24 is supported within the base plate 38 by fitting the spline ends 64 of the rotor hub 24 into the cylindrical holes 65 and is securely assembled between the base plate 38, the rotor shell 39 and the rotor hub 24. Maintain state. A press fit or possibly an interference fit between the end 64 and the bore 65 is sufficient for the desired support. The spline fit between the end 64 and the hole 65 is further designed to prevent relative rotational movement between the rotor hub 24 and the base plate 38. The effluent flow channel 6 is open to the interior space 95 of the base 21 defined by the side wall 96 of the base 21 by fitting the end 64 into the hole 65.
6 is formed. The side wall 96 is further provided with an outlet drain opening 97. With this drain opening, oil that has flowed out of the rotor 25 through the flow channel 66 can be drained out of the base 21. This is continuous for the circuit to or through the other elements of the corresponding engine or equipment. Lubricating oil used to drive turbine 29 through jet nozzles 27 and 28 also collects in the interior space and mixes with the oil exiting through flow channel 66. It is this mixed oil that exits through the outlet drain opening 97. Splash plate 98 post 8
6 and 88 are attached to the upper end surfaces 99 and 100, respectively.

In order to operate the centrifuge 20 shown in FIG. 1, pressurization (1.406 kg / cm ^{2 to} 6.327 kg / cm ² (2
0 PSI to 90 PSI)) The fluid stream (oil) enters the centrifuge base 21 through the inlet hole 82 and the main passage 83. Pressurized oil is supplied to the passages 84 and 85 and supplied to the passage 91 by the cylindrical hole 89. Post 86 defines an outlet orifice 103 in flow communication with jet nozzle 27. A similar outlet orifice 104 is defined by post 88 and is in flow communication with jet nozzle 28. The passages 84 and 85 are blocked at the ends, so that the inflow is pumped through the orifices 103 and 104, generating jets 27a and 28a, thereby driving the turbine 29, and consequently the rotor hub 24 and the rotor 25. Is driven rotatably. The high-speed fluid flow from the two jet nozzles is
The high rotational speed required for rotor 25 is generated to remove soot from the oil passed through rotor 25 at the desired speed. The required speed is a function of the outer diameter of the cone stack, as discussed above.

In a preferred embodiment, the jet nozzle 27
And 28 each have an exit orifice size of about 2.4.
6 mm (0.09 inch). Each nozzle is internally tapered to smoothly transition to the exit orifice diameter in order to generate a unique, stable jet with a turbulent energy of minimum and maximum possible velocity. Turbine 29 converts the kinetic energy of the jet into torque, which is applied to rotor hub 24. As described above, various types or designs of turbines 29 are contemplated within the scope and teachings of the present invention. Turbines include downsized older Pelton turbines, modified half bucket turbines, and vane ring or "turgo" turbines. Of these, the modified half-bucket turbine is the preferred choice. The turbine is optimized for performance efficiency when the bucket speed is slightly less than half of the impinging jet speed. In an ideal design, the drive fluid "falls" from the bucket with near zero residual velocity,
It falls into the internal space 95 of the base and exits through the drain opening 97. 4.921kg / cm ² to obtain a 10000RPM target speed of a jet of (70 PSI), and sends torque 5.50cm / kg (1 in / lb has a bucket pitch diameter 28.96mm (1.14 inches) )
The use of a turbine 29 designed to be is a design feature of this embodiment. In such a specification,
The pumping power (parasitic) loss for energy is only 15kgm /
s (1HP) (for the engine size under consideration of these conditions,
3% or less).

The oil entering through the passage 83 further flows upward through the cylindrical hole 89 into the passage 91 of the shaft 23. This upward flow exits through the throttle passage 93 into the shaft 23. In a preferred embodiment, the diameter of the exit orifice of passage 93 is 1.85 mm.
(0.073 inches), which limits the flow through the rotor 25 to about 0.6 gallons per minute. The flow through the rotor is between 0.757 liters and 1.514 liters per minute (0.2 gal.
Tests have shown that spikes with high torque resistance occur when the pressure is 4 gallons. 2.27 per minute
One liter (0.6 gallon) flow does not have this problem. An important feature of the present invention is that it throttles the incoming flow by using a passage 93 located adjacent the inlet end 107 of the rotor hub 24.
In the example of FIG. 1, the rotor hub 24 extends upward from the base 21 and the base plate 38 to the region of the mounting nut 61 at the upper end or top of the vessel shell 39.
The lower end 107 of the rotor hub is an inlet end intended to define a flow path as incoming oil enters at the hole 82 and flows inward and upward from there.

By arranging the throttle passage 93 at the inlet end 107 of the rotor hub, the inside of the rotor hub
8 so that standard deep groove sealed roller bearings can be used at the upper roller bearing 34 and lower roller bearing 35 locations. The use of these types of roller bearings significantly reduces rolling resistance compared to prior art (old) journal bearings. If the internal pressure in the interior 78 of the rotor hub 24 is higher than present in the present invention due to throttle effects, a journal bearing is required. This is because journal bearings can withstand high pressures. The problem is that the level of rotational resistance of the journal bearing, which limits the rotational speed that the rotor 25 can reach, is quite high. as a result,
The soot removal efficiency is greatly reduced, resulting in a design with much lower efficiency, and a design that is totally unacceptable when soot control is the goal. Add throttle action to the flow, internal 78
Reducing the internal pressure in the chamber has an attendant effect. In the centrifuge design according to the present invention, the use of roller bearings allows for low resistance, high rotational speeds, and thus, in the present invention, 10,000
Speeds on the order of RPM (or higher) can be obtained. It has been found that such a rate is required for efficient soot removal.

After exiting the shaft throttle passage 93, the process fluid (oil) travels upwardly through the center or interior 78 of the rotor hub 24 between the shaft 23 and the hub 24. A plurality of outlet holes are provided near the upper portion of the hub 24. These holes have a total of 8 holes in the preferred embodiment.
Individual. The flowing oil passes through each of these outlet holes 79 and the flow is conveyed by a flow distribution plate provided with radial vanes that accelerate the fluid tangentially.
Pointed on and around the stack.

The flow is distributed across the cone stack through vertically aligned cone inlet holes,
It flows radially inward toward the hub through the gap in the stack. The cone stack is firmly supported by the rotor hub base plate. When reaching the outer diameter of the hub, the flow passes downward through aligned notches provided in the inner diameter of the cone and exits the interior volume 73 through the flow channel 66. As a variation on this configuration, base plate 38 may be a one-piece design with perforated holes for fluid outlet channels. It is important that the flow exits the flow channel 66 as close as possible to the axis of rotation. This is due to the resistance due to centrifugal "pumping" energy loss which prevents outflow at high tangential velocities which increases in proportion to the radius /
This is to prevent a reduction in speed. Furthermore,
The effluent must leave the cone stack assembly so that it does not contact the outer surface of the base plate. As a result, Rob (ro
b) Energy is lost and "sling" at high speed from the outer diameter of the rotor base. This result is obtained by allowing the oil to flow through the flow channel 66 to a location below the splash plate 98, thereby causing the spray of oil to move downward and away from the rotating rotor hub 24 so that the drain opening 97 Deflect towards.
In the alternative design, if a splash plate is not used, the spilled oil is applied to the base plate so that it does not re-entrain on the surface of the rotating rotor when the oil scatters radially outward from the exit point. You need to start from a lower point than the lowest point. As described above, the "clean" process fluid is mixed with the drive fluid and drains out of the housing base 21 by gravity through the drain opening 97.

Referring to FIG. 9, a modified cone stack centrifuge 120 is disclosed. Note that the centrifuge 120 has a structure that is very similar in many respects to the cone-stack centrifuge 20 of FIG. The major differences between cone stack centrifuge 120 and cone stack centrifuge 20 include the design and relationship of base 21, shaft 23, cylindrical bore 89, and main passage 83. Comparing these parts of the centrifuge 20 with the corresponding parts of the centrifuge 120 reveals the following differences. In the design of FIG. 1 for centrifuge 20, main passage 83 is in direct flow communication with hole 89 in base hub 87. As shown, the holes 89 do not extend axially through the main passage 83, but effectively intersect in a T-shape there. In the design of FIG. 9, there is no flow communication between the cylindrical hole 121 in the base and the main passage 122. Instead, the lower end or base 123 of the shaft 124 of the centrifuge 120 is
Extending axially beyond zero, the shaft 124 extends through the main passage 122 and exits through a pilot extension 125 of the cylindrical bore 121. The shaft 124 is shown as a separate component in FIG. This pilot hole extension 12
5 crosses the main passage 122 as shown in FIG.
Is axially aligned with the upper portion of the cylindrical hole 121 above. The design of the base 126 of the centrifuge 120 is shown in FIG. The base 123 of the shaft 124 forms a flow path extending from the inlet hole 128 to the throttle passages 129 and 130. Here, the turbine 29 is given the reference number 134, but the design is basically the same. In FIG. 10, a turbine of a variant of the split bucket configuration is shown as turbine 134a.

The shaft 23 has a single throttle passage 9
3, whereas shaft 124 (see FIG. 9) includes two throttle passages 129 and 130. This is because in the embodiment of FIG. 9, almost all points upstream of passages 129 and 130 can throttle the incoming oil flow, preferably outside the centrifuge.
As a result, passageways 129 and 130 need not serve as a single throttle means. In FIG. 1, the incoming oil is also used to drive the turbine 29, and adding throttle to the flow outside the centrifuge will adversely affect the speed of the turbine. For this reason, the flow to the rotor 25 is throttled by the passage 93. It is easier to perform the throttle function in one passage compared to using two passages. For this reason, in the embodiment of FIG. 1, only one passage 93 is provided.

Since the internal passage through the shaft is not in flow communication with the main passage 122, the incoming flow (oil) at the inlet 128 is not used to drive the turbine 134. Turbine 134 is, in fact, the same as turbine 29, and the remainder of centrifuge 120 is substantially the same as centrifuge 20, except as described herein. Pressurized fluid is introduced into the main passage 122 via the inlet passage 137 to drive the turbine 134 with the jet nozzles 135 and 136. In a preferred embodiment, the pressurized fluid (ie, the driving fluid) is a gas. The pressurized gas follows the same path as the oil of FIG. 1, but does not flow into passage 127, and
Not introduced into stack assembly 138.

The pressurized gas is supplied to the passage 139 of the post 140,
A notch or a depression is provided at a position 141 of the base 123 of the shaft 124 so as to finally flow into the jet nozzle 136. This is to allow the pressurized gas to freely pass around the base 123 of the shaft 124. The passage 142 of the post 143 is
It communicates with the passage 122 to deliver pressurized gas to the jet nozzle 135. O-ring 144 is base 12
3 and a pilot hole extension 125. The inlet hole 128 is provided with an internal thread for connecting an input conduit for delivering a fluid to be introduced into the cone / stack assembly.

The gas (typically air) used to drive the turbine 134 of FIG. 9 must be released from the centrifuge 120 to the atmosphere. Although various vent designs and positioning are suitable for this function, it is important to first separate the oil mist mixed with air. For this purpose, a coalescer 150 is mounted on the bell housing 151 and the area around the outlet 152 is sealed. As the spray mist or aerosol of air and oil exits through outlet 152, oil is separated from air inside coalescer 150. The air then passes into the atmosphere, and the oil slowly drips back into the centrifuge. Inside the coalescer 150, a metal mesh is provided, or in a variant, a synthetic woven or non-woven mesh. All of these meshes are well known in the art.

Reference has been made herein to various types and designs for the turbine 29 and corresponding buckets. These include an older Pelton turbine 29a with individual buckets 32a having a split bucket configuration (see FIG. 2) and a modified half bucket turbine 29 with buckets 32.
(See FIG. 1). Either type of impulse turbine is suitable for the embodiment of FIGS. 1 and 9 and the variants of FIGS. 2 and 10. Although the schematic diagram of FIG. 3 is shown as turbine 29, it is intended to provide a suitable general illustration of turbines 29 and 29a.

In the discussion of other variations and modifications of the turbine 29, reference will be made to vaning or Targo turbines. The individual vanes of such a turbine may be arranged in virtually any diameter, but if the vane circle diameter increases beyond the bucket diameter shown for turbine 29, the gas The efficiency associated with the drive mode of operation is important. For gas driven centrifuges, vane ring type turbines are preferred. It is known that the optimum vane speed is equal to half the jet speed, and based on choked flow (sonic jet), it is preferable to arrange the gas driven vanes over a large diameter.

Therefore, FIG. 13, FIG. 14 and FIG.
Shown is a vane ring turbine 160 formed by attaching individual vanes 161 to the outer surface of a generally cylindrical portion 162a of a rotor shell 162 adjacent a lower edge 163. Each vane 161 has a concave impact surface 164.
And has a curved form. For this type of vane, the jet nozzle 165 may be at 5 ° to 2 ° relative to the vane centerline.
Pointed at a predetermined angle of 0 °. This angle substantially coincides with the leading edge angle of the vane 61. Jet nozzle 16
5 delivers a jet of air from passage 166. The jet impinges on and rotates the vanes, and thus drives (rotates) a rotor mounted on the shaft via bearings.

In order to operate the centrifuges of FIGS. 9, 10 and 13 in a gas-driven manner, the gas jet has a sonic velocity (about 0.9).
12 kg / cm ² (about 13 psig). Optimal vane speed for maximizing kinetic energy (Fig. 1
3) is about 0.4 times the jet speed, which is about 440 feet per second (for a sound speed of 1100 feet per second). 18.5 diameter rotating at 10,000 RPM
For a 42 cm (7.3 inch) rotor, the vane speed (vanes 161 are located around as shown in FIG. 13) is about 320 feet (97.536 m) per second. This speed is "slower" than the optimum speed.

The type of turbine vane (vane ring) used for the centrifuge of FIG. 13 is the modified half bucket type and split bucket turbine type of the centrifuge embodiments of FIGS. 2, 9 and 10. Can be used instead of The efficiency depends on the type of turbine used, the location of the turbine, the diameter of the rotor, the drive medium and the jet speed.

According to another embodiment of the present invention, the stationary jet nozzles 27 and 28 of FIG. 1 and the stationary jet nozzles 135 and 136 of FIG.
(See FIG. 16) at the inlet of each jet nozzle. Each flow hole 170a is defined by a hexagonal outer wall, and the insert 170
Extends over the entire length of The function of the insert 170 is to straighten the flow by eliminating or reducing inlet turbulence. Use of the insert 170 greatly improves the consistency and stability of the flow of the jet exiting the nozzle and directed to the turbine. The honeycomb insert 170 may be used in conjunction with a jet nozzle 165 if inlet turbulence is an issue.

With continued reference to FIGS. 1 and 9, each of the corresponding stationary jet nozzles 27 and 28 and 135 and 136 has a corresponding mounting post (86, 8).
8, 140 and 143) and assembled. Each mounting post defines an internal flow passage in communication with the inlet of its corresponding jet nozzle. FIG.
FIG. 4 is a schematic diagram illustrating a jet nozzle and mounting post for purposes of describing inlet turbulence and positioning and function of the insert 170.

With further reference to FIG. 18, the central flow axis 171 of the exemplary jet nozzle 172 is substantially perpendicular to the central flow axis 173 of the flow passage 174 of the mounting post 175. In fact, from passage 174 through nozzle inlet 17
The flow to 6 needs to bend at a right angle. The resulting turbulence is further complicated by the nature of the mounting post closed end 177 and, in some cases, the inlet 176.
A backflow that returns toward is generated.

If there is turbulence at the inlet 172 of the jet nozzle 172 (partially due to a 90 ° turn in the flow), then the outflow will impinge on the turbine bucket (see FIGS. 1 and 9). Will break. If the jet effluent breaks before hitting the turbine buckets, the efficiency of the turbine is reduced. Low turbine efficiency results in lower turbine speeds than desired for this particular application, increasing pumping of lubricating oil to seek and maintain the desired speed, and increasing power consumption.

It has been found that one of the key factors contributing to optimal impulse turbine efficiency is to provide a stable and consistent liquid jet from each jet nozzle when hitting a turbine bucket. When the effluent is broken, it appears as droplets and spreads in a fan-like pattern immediately upon exiting the jet nozzle, thereby greatly reducing jet quality and reducing turbine efficiency. Breakdown of the effluent reduces the desired thermodynamic efficiency of 50% to 60% to 25% to 35%.

[0048] The honeycomb insert 170 improves turbine efficiency. This is due to the improved consistency and stability of the liquid jet directed to the turbine bucket. The insert 170 has a flow of the jet nozzle 1
The flow is redirected to the inlet 176 so that it is straight in the direction of the 72 tapered outlet 178. This allows
Furthermore, a stratified outflow condition occurs at the throat of the nozzle, forming a consistent and stable outflow jet. This improvement significantly increases the efficiency of the turbine, which can generate a centrifugal force that provides the desired speed with low power consumption and lubricating hydraulic delivery.

The insert 170 has a thickness of about 8.9 mm (0.9 mm).
35 inches) of relatively thin aluminum material. Each of the individual cells 170a (hexagonal holes) is approximately 1.09 mm (0.043 inches) across the opposing flat sides. The insert 170 has a length such that it is fully inserted into the nozzle 172 up to the position of the throat where the inlet opening begins to taper. The opposite end of the insert 170 extends beyond the end of the nozzle 172 and into the passage 174, as shown in FIG. Surface 1 of insert 170
The outer diameter of 70b is approximately 6.35 mm (0.25 inches) and is sized to fit snugly into jet nozzle inlet 176.

An optional embodiment for the insert 170 includes using a molded plastic (see FIG. 17) or a die cast metal such as Zn, Mg, or Al. The metal of these variants forms the long and narrow capillary (cylindrical) passage 1 described above in order to generate the desired laminar flow.
70d is formed. The diameter of each passage 170d is approximately 0.8
6 mm (0.34 inch).

Other modifications of the insert 170 include:
This involves using a very coarse sintered metal plug or woven wire mesh disk attached to the nozzle inlet 176.

While the invention has been illustrated and described with reference to the accompanying drawings and the foregoing description, these are examples only and are not intended to be limiting. While a preferred embodiment has been shown and described, it will be appreciated that all variations and modifications thereof that fall within the scope of the invention are desired to be protected.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a cone stack centrifuge according to an exemplary embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of a cone stack centrifuge according to another embodiment of the present invention.

FIG. 3 is a schematic plan view of an impulse turbine constituting a part of the cone-stack centrifuge of FIG. 1 and a jet nozzle cooperating therewith.

4 is a sectional front view of a modified half bucket used as part of the impulse turbine of FIG. 3 used in the cone stack centrifuge of FIG. 1;

FIG. 5 is a perspective view of the half bucket of FIG. 4;

FIG. 6 is a front sectional view of a central shaft constituting one part of the cone stack centrifuge of FIG. 1;

FIG. 7 is a front sectional view of a rotor hub constituting one part of the cone-stack centrifuge of FIG. 1;

FIG. 8 is a plan view of the rotor hub of FIG. 7;

FIG. 9 is a sectional view of a cone-stack centrifuge according to a modification of the present invention as viewed from the front.

FIG. 10 is a partial front sectional view of a cone stack centrifuge according to another embodiment of the present invention.

FIG. 11 is a front sectional view of a central shaft constituting a part of the cone stack centrifuge of FIG. 9;

FIG. 12 is a front sectional view of a base constituting a part of the cone-stack centrifuge of FIG. 9;

FIG. 13 is a front sectional view of a vane ring type impulse turbine suitable for use as part of a cone stack centrifuge according to the present invention.

14 is a partial plan view of the vane ring type turbine of FIG.

FIG. 15 is a schematic diagram of one vane and a cooperating nozzle jet of the vane ring type turbine of FIG.

FIG. 16 is an end view of an end face of a jet nozzle insert for use as a component of a cone stack centrifuge according to the present invention.

FIG. 17 is an end view of another jet nozzle insert for use as part of a cone stack centrifuge according to the present invention.

18 is a longitudinal sectional view of a jet nozzle incorporating an exemplary mounting post and the jet nozzle insert of FIG.

[Explanation of symbols]

Reference Signs List 20 cone / stack centrifuge 21 base 22 bell housing 23 shaft 24 rotor hub 25 rotor 26 cone / stack 27, 28 jet nozzle 27a, 28a jet 29 deformed Pelton turbine 32 bucket 33 wheel 34, 35 roller bearing

 ──────────────────────────────────────────────────続 き Continuation of the front page (71) Applicant 594110468 100 BNA Corporate Center, Suite 500, Nashvillle, Tennessee 32717, U.S.A. S. A.

Claims (5)

[Claims] 1. A cone-stack centrifuge for separating particulate matter from a circulating fluid, the cone-stack centrifuge having a cone-stack and a hollow rotor hub, and configured and arranged to rotate about an axis. A rotor, a fluid inlet, a first passage, a second passage connected to the first passage, and a hollow base hub, wherein the fluid inlet is connected to the hollow base hub by the first passage. A shaft assembly attached to the base hub and extending through the rotor hub, wherein the fluid is disposed within the shaft center tube.
A shaft central tube having a passage for delivery from the passage to the cone stack, and a shaft positioned between the rotor hub and the shaft central tube for rotating the rotor about the shaft central tube. A bearing; an impulse turbine attached to the rotor; and an impulse turbine connected to the second passage and configured to direct the jet of the fluid by the impulse turbine that sequentially transmits rotational motion to the rotor. A cone stack centrifuge comprising: a jet nozzle and an insert for reducing the inlet turbulence, the insert being provided in the jet nozzle for defining a flow direction. 2. The impulse turbine includes a plurality of independent turbine buckets, each designed in the shape of a half bucket, the buckets being configured and arranged to be acted upon by the jet of the fluid. Yes,
The cone stack centrifuge of claim 1. 3. The cone stack centrifuge of claim 2, wherein said flow direction defining insert defines a plurality of spaced apart flow holes. 4. The impulse turbine has a plurality of independent turbine buckets, each designed in the form of a split bucket, the buckets being configured and arranged to be acted upon by the jet of the fluid. The corn stack centrifuge of claim 1, wherein 5. The cone-stack centrifuge of claim 4, wherein said flow direction defining insert defines a plurality of spaced-apart flow holes.